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Log on to any muscle-building forum and you'll discover fiercely fought 'discussions' over the grey areas of building muscle. The pros and cons of training methods, nutritional strategies and workouts are endlessly debated - but there are some things in the muscle universe that are black and white. These are the seven deadly muscle sins.
The Devil says: Go on son, have another tequila slammer. It's Friday night and all workouts, no play makes Johnny a dull boy.
The Good Book MF says: A drink or two with food is fine but bingeing on booze has several disastrous consequences, especially after exercise. Despite being packed with more calories than a chocolate salad, the sugars in alcohol are in a form that can't be immediately used by your muscles to kick-start recovery. Because you're drunk, you won't notice or care that you're hungry and your body will turn to the most readily available energy store in your body - muscle tissue. At this point your body enters a catabolic state where you're literally eating yourself to survive. And a hangover will disrupt the glucose pathways in your body, weakening your muscles and further delaying the recovery process.
The Devil says: Cor, look at that pot belly and those spindly little arms - you'll never pull on the beaches like that. Get to the gym and don't come back till you've worn your hands raw, you slob.
The Good Book MF says: Working out for too long or too often is actually worse than working out too little. After 45 minutes or so, the energy stores in your muscles and liver are exhausted, which means two-hour workouts are just counterproductive. The process of muscle-building relies on you breaking down muscle tissue and then giving it at least two days to rebuild and grow. Hard training also weakens your immune system. 'Never train if you still have muscle soreness, ' warns Steve Backley, three-times Commonwealth gold medallist in the javelin. 'Watch out for signs of overtraining such as lethargy and all your food tasting the same.'
The Devil says: Call that a weight? Are those dumb-bells made of polystyrene, sunshine?
The Good Book MF says: Naturally you should aim to progress, but most people try to lift too much too soon. As well as risking injury, it will have less impact on your muscle mass than lifting weights with which you can actually complete a set. This is because to get bulk up you need to place the muscle under tension for 45-60 seconds per set, which means being able to complete around eight reps. 'Park your ego at the door of the gym,' says EIS strength and conditioning coach Nick Grantham. 'It might not look like you're working as hard as someone else, even though by concentrating on doing the correct movement with a sensible weight you'll get better results.'
The Devil says: You're exercising your legs? What for? No one looks at them anyway. Get to the bench press, now!
The Good Book MF says: Building a stronger, better body isn't about pumping up selected muscle groups because they look good in the mirror. Overdeveloping some muscles at the expense of others can lead to strength imbalances and posture problems, leaving you looking like you've dropped a couple of rungs on the evolutionary ladder. You should follow a balanced workout plan. 'A classic conditioning error isdoing too many pushing exercises - such as the bench press and the squat - and not enough pulling ones, which can create real muscle imbalances, ' says Backley.
The Devil says: Lift fast. Load up the bar and go as quickly as possible. Otherwise you will stand out like Jade Goody in a sari.
The Good Book MF says: You should lift a weight, under control, through a muscle's entire range of motion. What you shouldn't do is swing a weight around, using momentum, rather than force, to lift it. This will make you look like you're flying through your workout but it won't help you achieve your goals. 'Look for symmetry even when lifting to failure, and always retain balance and control because this is when you test your posture under pressure, ' says Backley.
The Devil says: So you're busy? So what? It's murder down here, but do you here me whining? No. So cancel your social life, ignore calls from your missus and do that chest workout.
The Good Book MF says: The body's stress hormone, cortisol, is at its highest level in the morning and it decreases slowly throughout the day as you get closer to sleep. But a stressful lifestyle and cramming workouts into late evening raises the level again. While cortisol helps you get more done, faster, it also makes your body burn muscle tissue as fuel.
The Devil says: You've just burned hundreds of calories in the squat rack, so of course a Mars Bar isn't going to make you fat. You'll probably sweat that off on the bus home. Go on, get stuck into that doner kebab while you're at it. Lovely!
The Good Book MF says: Just because you're exercising well doesn't give you a 'get out of jail free' junk food card. If you pile on simple carbs (sugars) and fatty foods after a workout you'll get a massive spike of energy, most of which will just be turned into fat without providing your body with the nutrients it needs to convert your workout into brand new muscle. 'To rebuild your muscles you need to take on board lean protein and carbs in a 3:1 ratio straight after your workout,' says Grantham, 'because if you wait until after you've showered and made your dinner you will have missed your nutritional window of opportunity.'
Steve Backley has designed his own training system at pactraining.co.uk. He is part of the UK Athletics & Norwich Union Mentoring Programme for British athletes.